Add simple random text generator

src/main/java/bullshit_paper/MarkovChain.java

@@ -0,0 +1,76 @@
+package bullshit_paper;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map.Entry;
+import java.util.Random;
+
+public class MarkovChain {
+	private HashMap<String, LinkedList<String> > graph;
+
+	MarkovChain(){
+		graph = new HashMap<>();
+	}
+
+	public void build(List<String> sentences){
+
+		for(String s: sentences){
+			List<String> cur = Parser.parseSentence(s);
+			cur.add(".");
+
+			for(int i=-1; i<cur.size()-1; ++i){
+				LinkedList<String> tmp;
+				String from;
+
+				if(i == -1){
+					from = "#";
+					tmp = graph.get(from);
+				}
+				else{
+					from = cur.get(i);
+					tmp = graph.get(from);
+				}
+
+				if(tmp == null){
+					tmp = new LinkedList<String>();
+				}
+
+				tmp.add(cur.get(i+1));
+				graph.put(from, tmp);
+			}	
+		}
+
+		for(Entry<String, LinkedList<String>> entry: graph.entrySet()){
+			LinkedList<String> tmp = entry.getValue();
+			Collections.shuffle(tmp);
+			graph.put(entry.getKey(),tmp);
+		}
+
+	}
+
+	public String generateRandomText(int length){
+		StringBuilder builder = new StringBuilder();
+		Random random = new Random();
+
+		for(int i=0; i<length; ++i){
+			String cur = "#";
+
+			while(cur != "."){
+				LinkedList<String> list = graph.get(cur);
+				int size = list.size();
+				cur = list.get(random.nextInt(size));
+
+				if(cur != "."){
+					builder.append(" "+cur);
+				}
+			}
+
+			builder.append(".");
+		}
+
+		return builder.toString();
+	}
+
+}